def get_greeting(catchphrase, days_since_spoken) :
    if days_since_spoken < 1:
        greeting = "哈哈，又看到你啦"
    else:
        greeting = "很高兴见到你"
    return greeting + ", " + catchphrase + "."

last_chatted = 6
response = get_greeting ("同学", last_chatted + 1)

last_chatted = 0
get_greeting("小土豆", last_chatted)
print("问候: " + response)